const obj = {
  [Symbol.toPrimitive](hint) {
    if (hint == "number") {
      return 10;
    }
    if (hint == "string") {
      return "hello";
    }
    return true;
  },
};

console.log("相加:", 5 + obj);
console.log("等等与:", 5 == obj);
console.log("不等于:", 5 != obj);
